How to have or not menu on specific page

[JOduMonT]

I understand we could generally drop the menu option and then activated it for a specific page by
specifying in params.yaml

header:
  navbar:
    enable: false

and then in every page I build adding

-----
params:
  header:
    navbar:
      enable: true
-----

but the opposite doesn't seam to work; such as if I want to hide the navbar only in few specific pages

How I would do that ? because that in my index.md did'nt work

-----
params:
  header:
    navbar:
      enable: false
-----